Pyrotechnic-operated fire extinguisher



Nov. 21, 1950 E. R. SCHOLZ 2,530,633

PYROTECHNIC-OPERATED FIRE EXTINGUISHER Filed April 11, 1949 EDWARD R. SCHOLZ INl 'ENTOR.

Patented Nov. 21, 1950 PYROTECHNIC-OPERATED FIRE EXTINGUISHE R Edward R. Scholz, Elmira, N. Y., assignor to American-La France-Foamite Corporation, Elmira, N. Y., a corporation of New York Application April 11, 1949, Serial No. 86,783

8 Claims. (Cl. 169-26) This invention relates to fire extinguishers of the kind in which a liquid extinguishing medium, such as methyl bromide, is expelled from its container by gas evolved from the burning of a so-called powder grain.

The general object of the invention is an extinguisher of this type which is reliable in operation, of simple construction, and so organized as to apply the evolved gas effectively to discharge the extinguishing medium.

The invention will be readily understood from the following description of the preferred embodiment illustrated in the accompanying drawings, of which:

Fig. 1 is a partially sectioned elevation of the extinguisher; and

Fig. 2 is a partially sectioned detail of the pyrotechnic charge unit.

In this preferred embodiment, the extinguisher comprises a spherical container l for the liquid, having a bottom outlet shown as consisting of an el bow fitting 2, the vertical bore of which is normally closed by a diaphragm 3. As will be understood, this diaphragm is designed to be ruptured by the internal pressure upon ignition of the powder grain, the ruptured portion being blocked from passing beyond the neck portion of the fitting 2 and into the discharge line by the perforated sleeve 4.

The pyrotechnic charge is mounted in the upper part of the container. As shown in Fig. 2, it consists of a hermetically sealed container 5, proof against deterioration, comprising a powder grain 6 and, above it and separated from it by a screen I, an igmter charge 8 of black powder. Two electric 'squibs 9 are inserted in the latter charge to ignite it. A contact I!) is sealed in the cover of the unit. The element Ia is a so-called grid, comprising a piece of wire which serves to locate the powder grain 6 and space it slightly from the bottom of container 5, to facilitate burning of the grain from both ends rather than from the top only and thereby increase the rate of gas generation. The pressure developed within the charge container I is suflicient to rupture part of the bottom wall over an unsupported area, as below described.

Seated in an opening in the upper part of liquid container I and secured in place, as by welding, is an open-topped container cup H in which the pyrotechnic unit is supported. The unit is mounted with clearance between at least one of its walls and the container cup, as by supporting it on a floor member l2. The latter has a central opening around which is a depending flange l3 having large openings l4 opening into the annular space surrounding the flange. Thus, the central portion of the bottom of the charge container 5 is unsupported; and it is this area which bursts through when the charge is set off. The ruptured or sheared-out portion of the bottom wall of container 5 moves down into the space within flange I3, with no substantial obstructing of discharge openings H.

The container cup II is provided with a series of restricted metering orifices which open into the interior of liquid container I and which serve to restrain and thereby prolong the gas discharge. As shown, these small metering orifices, marked l5, are located in the lower part of the side wall of container cup II. It has been found that, by discharging the gases evolved from the pyrotechnic unit into the annular space surrounding flange l3 and thence through the metering orifices, much of the flame temperature of the burning powder is dissipated and that the metering orifices are thereby protected against burning.

Supported in the liquid container is a baflle which serves to intercept the discharge from the metering orifices and prevent the jets of gas from directly striking the spherical "wall of the liquid container and tending to sweep around such wall toward the bottom outlet, rather than, as desired, serving as a gas piston actingon the surface of the liquid. In the illustrated extinguisher, this ballie is in the form of a cup l6 telescoped up over the bottom of the charge cup II and secured to it, as by welding. The wall of cup I6 is spaced from but extends up over the metering orifices, so that the velocity of the gas jets striking the battle is reduced and the gas diverted upwardly toward the top of the liquid container.

Lastly, it will be noted that container cup H is adapted to be closed and the charge unit sealed in place, by a screw stopper l1, through which passes a binding post l8 for engagement with contact III on the charge unit.

In the light of the foregoing description, which will be understood to be illustrative, the following is claimed:

1. A container for fire-extinguishing liquid, having a rupturable diaphragm closure at its lower end; an open topped. pyrotechnic container cup seated in an aperture in the container wall at its upper end and depending into the container, said cup having radially directed metering orifices spaced around the lower part of its side wall; a charge-supporting floor member in the container cup having a central opening and, around the opening, a depending flange spacing the floor member above the said metering orifices and forming an annular chamber Within the said lower part of the container cup, said flange having openings of greater area than the said meter orifices; a baflle cup secured to the outside of the bottom of the container cup, with its side wall outwardly spaced from and extending upwardly beyond the said metering orifices; a sealed, pyrotechnic charge container seated in the container cup on said floor member, said charge container having a rupturable bottom wall; and a closure cap for the open top of the container cup.

2. A container for fire-extinguishing liquid, having a rupturable disphragm closure at its lower end; a pyrotechnic container cup mounted on the container wall at its upper end, said cup having radially directed metering orifices spaced around the lower part of its side wall and opening into the container; a charge supporting floor member in the container cup having a central opening and, around the opening, 9. depending, apertured flange spacing the floor member above the said metering orifices and forming an annular chamber within the said lower part of the container cup; a bafiie wall surrounding the container cup in the line of discharge from the metering orifices; a sealed pyrotechnic charge container seated in the charge cup on said floor member, said container having a rupturable bottoai wall; and a closure cap for the container cup.

3. A container for fire-extinguishing liquid, having a discharge outlet at its lower end; a pyrotechnic container cup mounted on the container at its upper end; a charge supporting floor member in the cup having an opening therethrough and, between the opening and the cup wall, a depending, apertured flange spacing the floor member above the bottom of the said cup; the pyrotechnic container cup wall having gas metering orifices opening into the container from the space between the cup wall and the apertured flange; a bafile supported within the container, spaced from but in the line of discharge from said metering orifices; a sealed pyrotechnic charge container seated in the charge cup on said floor member, said container having a rupturable bottom wall; and a closure cap for the container cup.

4. A container for fire-extinguishing liquid, having a discharge outlet at its lower end; a pyrotechnic container cup mounted on the container at its upper end; a charge supporting floor member in the cup having an opening therethrough, said floor member being spaced above the bottom of the said cup; the pyrotechnic container cup wall having laterally directed gas metering orifices opening into the container from the space beneath the floor member; a battle supported within the container, spaced from but in the line of discharge from the said metering orifices; a sealed pyrotechnic charge container seated in the charge cup on said floor member: and a closure cap for the container cup.

5. A container for fire-extinguishing liquid, having a discharge outlet at its lower end; a pyrotechnic container cup mounted on the container at its upper end, said cup having gas metering orifices through its wall and opening into the container; a baflie supported within the container, spaced from but in the line of discharge from the metering orifices; a rupturable, sealed pyrotechnic charge container seated in the container cup; and a closure cap for the container cup.

6. A container for fire-extinguishing liquid. having a discharge outlet at its lower end; a pyrotechnic container cup mounted on the container at its upper end; a charge supporting fioor member in the cup having an openin therethrough and, between the opening and the cup wall, a depending, apertured flange spacing the floor member above the bottom of the said cup; the pyrotechnic container cup wall having gas metering orifices opening into the container from the space between the cup wall and the apertured flange; a sealed pyrotechnic charge container seated in the charge cup on said floor member, said container having a rupturable bottom wall; and a closure cap for the container cup.

7. A container for fire-extinguishing liquid, having a discharge outlet at its lower end; a pyrotechnic container cup mounted on the container at its upper end and incorporating a charge supporting floor member having an opening therein, a depending wall portion encircling said opening and having laterally directed gas discharge openings therein; and a sealed pyrotechnic charge container seated in the charge cup on said floor member, said container having a rupturable bottom wall.

8. A container for fire-extinguishing liquid, having a discharge outlet at its lower end; a pyrotechnic container cup mounted on the container at its upper end; outwardly and upwardly directed gas discharge ducts leading from the interior of the said cup to the interior of the container; and a rupturable pyrotechnic charge container seated in the charge cup, a wall of the cup having an opening therein to define a rupture area for the charge container.

EDWARD R. SCHOLZ.

REFERENCES CITED UNITED STATES PATENTS Name Date Kauch June 8, 1926 Number 

